Hydrogen Sulfide

At normal concentrations, hydrogen sulfide has anti-inflammatory, antioxidant, and neuroprotective effects. The article does not define thresholds separating beneficial hydrogen sulfide signaling from problematic excess. Hydrogen sulfide levels are dysregulated in mood and neurodegenerative disorders, but studies disagree on whether levels are high or low. Hydrogen sulfide is described as a partner gasotransmitter that may extend nitric oxide support. Hydrogen sulfide may help nitric oxide release from nitrosothiol stores and extend nitric oxide effects through PDE5 inhibition. Hydrogen sulfide can be beneficial at physiological levels but harmful at excessive concentrations. Hydrogen sulfide is presented as beneficial in endogenous signaling contexts but potentially toxic or unpleasant at high levels or in gut overproduction. Elevated hydrogen sulfide can compromise gut and blood-brain barrier integrity and promote neuroinflammation. Gut microbes can produce hydrogen sulfide, which can enter the bloodstream and cross the blood-brain barrier.